Pregnancy of unknown location (PUL)
Information for women, birthing people, and their families
What does the term pregnancy of unknown location mean?
Following your appointment today, you may have been told that you have a pregnancy of unknown location. This term is used when you have a positive pregnancy test but we are unable to see a pregnancy on an ultrasound scan. This can be a confusing and frightening time for women, birthing people, and their partners. We understand it can be difficult to take in the information explained to you at your appointment. The aim of this leaflet is to provide you with clear information about your diagnosis, and explain what happens next and where you can get support, if you have any concerns during the investigating process.
What does this mean?
There are three possible reasons why we are unable to see the pregnancy on a scan.
The pregnancy is too early to be seen on a scan
Pregnancy tests are now extremely sensitive and can sometimes detect the pregnancy hormone as early as a few days after conception. However, a pregnancy sac may not be visible on ultrasound until approximately three weeks after conception (which is about five weeks after your last period). This means that the pregnancy is in the womb but it is simply too early to see it on a scan yet.
An early miscarriage has occurred or the pregnancy inside the womb is failing
If you have had period like bleeding, it is possible that the pregnancy has already miscarried from the womb and this is why it is no longer visible.
The pregnancy is outside of the uterus, most likely in the fallopian tube
This is called an ectopic pregnancy. This type of pregnancy is rare and the least likely possibility, however until we can identify a pregnancy within the uterus we cannot exclude the possibility of an ectopic. For this reason it is important that we investigate further, as an ectopic can be potentially life threatening if not treated in the early stages.
What happens next?
To help us find out what is happening in your pregnancy, we look at the level of pregnancy hormone (HCG) in your blood and how much it increases over a 48 hour period. The first blood test will be taken on the day of your appointment. You will be able to go home afterwards and should be contacted with the result later the same day, unless you have been told otherwise by the nurse. Arrangements will then be made for you to attend for another blood test 48 hours later.
In a normal early pregnancy that is within the uterus, we expect the hormone level to double after 48 hours. If this happens we will arrange a follow-up scan to confirm this. In almost nine out of every 10 cases, the doubling of HCG in 48 to 72 hours is associated with pregnancy in the uterus. However, an ectopic pregnancy cannot be completely ruled out, so you will need closer monitoring with ultrasound.
If a miscarriage has occurred then the level should fall. If this is the case we will provide you with information on miscarriage and ask you to carry out a urine pregnancy test at home in two to three weeks time. This is to check your hormones have returned to a pre-pregnancy level. In some very early pregnancies in the womb, which are not growing properly, the levels can stay the same or even rise slightly before they start to fall. To assess further, a repeat blood test may be needed after another 48 hours.
In an ectopic pregnancy the hormone level may increase but it will not double, it may even stay the same. If this happens, it does not mean that an ectopic has been confirmed, but that we need to investigate a bit more. To investigate further we may ask you to attend for a repeat blood test in another 48 hours. In some cases when the hormones are at a level when we would expect to see a pregnancy on a scan, you may be asked to attend earlier for a doctor to assess you.
Further advice
You may have mild abdominal cramping pains and some bleeding while you are having investigations. Paracetamol can be taken if needed, to help with the pain. If you are coping with your symptoms and you feel well, you can stay at home during this time.
However, if you develop increasing or persistent abdominal pains, that are not eased by paracetamol, or you suddenly start to feel unwell or faint, do not wait until your next appointment. Contact your Early Pregnancy Assessment Unit (EPAU) immediately on the numbers listed below or attend the Emergency Department (ED) at either Queen Elizabeth the Queen Mother Hospital (QEQM) Margate or William Harvey Hospital (WHH) Ashford for urgent assessment.
We are keen to support you during this difficult time, so if you have any questions or concerns, please contact one of the following units.
EPAU (QEQM), Monday to Friday 8am to 3:30pm; Saturday 8am to 2pm
Telephone: 01843 234469EPAU (WHH), Monday to Friday 9am to 3pm; Sunday 7am to 1pm
Telephone: 01233 616107Out of these hours please contact:
Birchington Ward (QEQM)
Telephone: 01843 234201Women’s Health Suite (WHH)
Telephone: 01233 651987